Kāneʻohe Bay, Hawaiian Islands, USA

Kāneʻohe Bay, at 45 km², is the largest sheltered body of water in the main Hawaiian Islands. The Bay is approximately 8 mi (12.8 km) long and 2.7 mi (4.3 km) broad, with a mouth opening of about 4.6 mi (7.4 km) and maximum depth of 40 ft (12 m) in the dredged channel. Features unique in the main Hawaiian Islands include one of only two barrier reefs (the other being the 27 mile barrier reef of Molokaʻi island) and extensive development of shoaling coral reefs within a large lagoon.